"Sub leasing" out P@40 space while being moral, ethical, legal, unstoppable, etc. is just kind of, well ... rude (and a bit greedy).
Yes. If he wants to get greedy about it, I know some people above him in line
By the time you are able to "punish" him by pushing him out you would also as a side effect punish ever single one of the very nice polite people below him by pushing all of them out.